difference between Null,Blank and Zero

Question

Please anyone can explain below quation, What is the difference between Zero,Blank and null?

Rajanikant Hawaldar · Answer

Zero is a number value. It is a definite with precise mathematical properties. (You can do arithmetic on it ...) NULL means the absence of any value. You can't do anything with it except test for it. Blank is ill-defined. It means different things in different contexts to different people. For example: 1)Someone could mean a zero length string value: i.e. one with no characters in it (''). 2)Someone could mean a non-zero length string value consisting of only non-printing characters (SPACE, TAB, etc). Or maybe consisting of just a single SPACE character. 3)In some contexts (where character and string are different types), someone could mean a non-printing character value. 4)Someone could even mean "anything that doesn't show up when you print or display it". The point is that "blank" does not have a single well-defined meaning. At least not in (native) English IT terminology. It is probably best to avoid it ... if you want other IT professionals to understand what you mean. (And if someone else uses the term and it is not obvious from the context, ask them to say precisely what they mean!)

Vijay Khatri · Answer

Here I am giving an informative example here that can make you understand about the concept you are confused about. NULL values are considered as unknown values. They are neither true nor false. On the other hand, “zero” is known value i.e, 0. Let’s get this clear with an example CHILDREN - BALLOONS C1 - 2 C2 - 0 C3 - NULL C4 - 3 C5 - 1 Now if we want to find the average balloons of 5 children, then average = 2+0+3+1/5 as we observe here number of children = 5 number of balloons = 4 as the NULL value of C2 is not at all taken into consideration while computing the average. Because NULL values are unknown values. But 0 value of C3 is taken into consideration while computing the average